1. Field of the Invention
This invention relates generally to a GPS-based system and method that displays different views of a target and, in particular, utilizes a user's selected source position to assist in displaying information about the target.
2. Description of Related Art
GPS systems have been used as navigation systems to location destinations. GPS systems have also been used in sports by participants in contests where position, location and distance to features are important. For example, U.S. Pat. No. 5,364,093 describes a GPS system and method for allowing a golfer to tell distance to a hole or other feature, and permits the course to track and manage golfers on the course. NASCAR with Sportsline has developed a GPS system mounted to cars for TV viewers to monitor a race.
GPS systems are becoming much more accurate, inexpensive and robust. GPS antennas and engines are fairly inexpensive and accurate with WAAS to less than 2 meters. In navigation use, the accuracy of GPS can be improved to centimeters, depending on the accuracy required, latency constraints, processing and bandwidth available, etc. Further, communication links are becoming very inexpensive and high bandwidth. For example, WiFi (802.11g) has modems with network signals approaching a 1 mile range, cost less than $5, with bandwidth of 54M bit/sec. Wi-max (802.16) has network signals approaching 30 miles with data rates as high as 70M bit/sec, but is more relevant to fixed installations Future versions of WiFi or other radio technology might be less than $1 with 10-100× bandwidths within a few years (as used herein WiFi refers to current and future versions of wireless local area networks (WLAN) based on the IEEE 802.11 specifications). Other radio technologies are also promising in many applications, such as Zigbee and Ultrawideband.
What has not been done in sports is an integrated GPS system for spectators to more fully enjoy a sport particularly at a remote location. For example, at a NASCAR race, the TV or radio viewing location limits his view of the race and is not his own unique perspective. While watching a race, the spectator might listen to a radio or watch a portable TV, but the perspective is the announcer's or TV angle. Such divergent perspectives—announcer versus personal—can be confusing. Further, a remote spectator might be most interested in the cars he is interested in—the ones near the 3rd turn. Other sports would benefit from a system that allows a spectator to more fully integrate the contest information with his desired viewing perspective. In addition to auto racing, football, yachting, horse racing, golf, hockey or any motor sport are candidates for the system and method hereof, especially as size and weight of GPS and radios accompanying a participant decreases.
U.S. Pat. No. 6,744,403 describes a GPS system for tracking objects, such as cars, at a sporting event. See also, U.S. Pat. No. 6,195,090; U.S. Patent Application Publication No. 2006/0105857; U.S. Patent Application Publication No. 2005/0259002. High data rate packet transmission is known, such as U.S. Pat. Nos. 6,894,994; 6,909,738; 6,885,652; 6,917,644; and 6,801,516. Examples of user interfaces, such as PDAs, cell phones, headsets, and the like are described, for example, in U.S. Pat. Nos. 7,053,780; 6,879,443; and 6,115,177. All references cited herein are incorporated by reference.
In navigation and locator GPS-based systems, what is lacking is an integrated GPS system for an individual user to gain situational awareness and to easily identify destinations or other areas of interest. That is, while a user might possess a GPS-enabled cell phone that transmits his position and gives text based directions to a destination, this information gives a very incomplete understanding to visually identify a destination. Such a user might have an overhead view of a map showing the position of the destination on the map, but leaves it up to the user to find and identify the destination.
A particular problem in the area of personal navigation is identifying a place of interest in a confusing environment, such as a crowded street. For example, a cell phone having a GPS might be enabled to identify that a destination is near, but the user cannot locate the destination because of the clutter or environment, e.g. a crowded street or neighborhood or obstructions to the user's line of sight. Users also have difficulty relating how a small mark identifying a place on a map correlates to their position or their view of the environment.
U.S. Pat. No. 7,002,551 describes augmented reality approaches based on digitized video camera or optical as follows:                Augmented Reality (AR) enhances a user's perception of, and interaction with, the real world. Virtual objects are used to display information that the user cannot directly detect with the user's senses. The information conveyed by the virtual objects helps a user perform real-world tasks. Many prototype AR systems have been built in the past, typically taking one of two forms. In one form, they are based on video approaches, wherein the view of the real world is digitized by a video camera and is then composited with computer graphics. In the other form, they are based on an optical approach, wherein the user directly sees the real world through some optics with the graphics optically merged in. An optical approach has the following advantages over a video approach: 1) Simplicity: Optical blending is simpler and cheaper than video blending. Optical see-through Head-Up Displays (HUDs) with narrow field-of-view combiners offer views of the real world that have little distortion. Also, there is only one “stream” of video to worry about: the graphic images. The real world is seen directly through the combiners, which generally have a time delay of a few nanoseconds. Time delay, as discussed herein, means the period between when a change occurs in the actual scene and when the user can view the changed scene. Video blending, on the other hand, must deal with separate video streams for the real and virtual images. Both streams have inherent delays in the tens of milliseconds. 2) Resolution: Video blending limits the resolution of what the user sees, both real and virtual, to the resolution of the display devices, while optical blending does not reduce the resolution of the real world. On the other hand, an optical approach has the following disadvantages with respect to a video approach: 1) Real and virtual view delays are difficult to match. The optical approach offers an almost instantaneous view of the real world, but the view of the virtual is delayed. 2) In optical see-through, the only information the system has about the user's head location comes from the head tracker. Video blending provides another source of information, the digitized image of the real scene. Currently, optical approaches do not have this additional registration strategy available to them. 3) The video approach is easier to match the brightness of real and virtual objects. Ideally, the brightness of the real and virtual objects should be appropriately matched. The human eye can distinguish contrast on the order of about eleven orders of magnitude in terms of brightness. Most display devices cannot come close to this level of contrast.        AR displays with magnified views have been built with video approaches. Examples include U.S. Pat. No. 5,625,765, titled Vision Systems Including Devices And Methods For Combining Images For Extended Magnification Schemes; the FoxTrax Hockey Puck Tracking System, [Cavallaro, Rick. The FoxTrax Hockey Puck Tracking System. IEEE Computer Graphics & Applications 17, 2 (March-April 1997), 6-12.]; and the display of the virtual “first down” marker that has been shown on some football broadcasts.        
U.S. Pat. No. 6,919,867 describes the state of the art in augmented reality approaches as follows:                Virtual reality is used in many diverse fields, such as kitchen design and military training Virtual reality immerses a user in a digital environment, where the user's perceptions of sight and sound are manipulated by a computer. While virtual reality provides inexpensive alternatives to building a mock-up of a kitchen or firing live ammunition during an exercise on a battlefield, virtual reality systems lack the sophistication of human perception.        Virtual reality systems have evolved into augmented reality based systems, where a user's perception of a real environment is augmented with information . . . .        An augmented reality system can be used to provide guidance to a user, for example, providing information during a surgical procedure. A view of a patient's internal anatomical structures may be overlaid onto a real view of the patient. The internal structures are determined and shown in a graphical representation registered with the view of the real patient.        A head-mounted display (HMD) is a desirable means to display an augmented view to a user. Various HMDs are depicted at http://www.cs.unc.edu/{tilde over ( )}us/web/headmounts.htm. A HMD allows the user to vary the viewpoint by turning his or her head. However, HMDs are typically cumbersome, especially over longer periods. The weight of a HMD may put a significant strain on a user's neck and back, especially if the user assumes a pose with a tilted head.        The prior art proposes that the difference between the user's natural eye-point and the viewpoint of the video camera is a concern. The prior art proposes designs which attempt to align an imaging camera with the user's line of sight. Designs have been proposed to further include beam combiners to align the optical axis of a camera and a user, e.g., A. Takagai, S. Yamazaki, Y. Saito, and N. Taniguchi, “Development of a Stereo Video-See-Though HMD for AR Systems,” IEEE and ACM Int. Symp. On Augmented Reality—ISAR 2000 (Munich, Germany, Oct. 5-6, 2000), pages 68-77. However, these systems do not address the comfort associated with wearing a HMD, particularly when the user assumes a pose with a tilted head.        For registration between the view of the real environment and the augmenting graphics, the user's viewpoint needs to be tracked. In prior art, head-mounted tracking cameras have been used for optical-see-through displays (where the user sees the real environment through a semitransparent display that shows additional graphics), but not for video-see-through displays. An example-of an optical-see-through HMD with two head-mounted tracking cameras in conjunction with a magnetic tracker is described by Thomas Auer and Axel Pinz in “Building a Hybrid Tracking System: Integration of Optical and Magnetic Tracking”, Proceedings of the 2nd IWAR'99, IEEE Computer Society, (IWAR'99, San Francisco, Oct. 20-21, 1999). In the case of video-see-through HMDs, a method has been proposed which uses the views captured by the imaging cameras for tracking, and a magnetic tracker. See State, Andrei, Gentaro Hirota, David T. Chen, William F. Garrett, and Mark A. Livingston. “Superior Augmented-Reality Registration by Integrating Landmark Tracking and Magnetic Tracking” Proceedings of SIGGRAPH 96 (New Orleans, La., Aug. 4-9, 1996); Computer Graphics Proceedings, Annual Conference Series 1996, ACM SIGGRAPH, pgs. 429-438. However, the tracking capabilities exhibited by the known prior art systems are not suitable in a practical setting for tasks needing precise graphical registration.        A video-see-through display can be head-mounted. Tracking, e.g., by optical means, can be added to enable augmented reality visualization. See: F. Sauer, F. Wenzel, S. Vogt, Y. Tao, Y. Gene, and A. Bani-Hashemi, “Augmented Workspace: Designing an AR Testbed,” IEEE and ACM Int. Symp. On Augmented Reality—ISAR 2000 (Munich, Germany, Oct. 5-6, 2000), pages 47-53.        Within the field of virtual reality, Fakespace Labs Inc. offers the BOOM (Binocular Omni-Orientation Monitor) personal immersive display for stereoscopic visualization on a counterbalanced, motion-tracking support structure. The BOOM utilizes opto-mechanical shaft encoders for tracking Mechanical tracking requires the boom to be stiff to achieve precise measurements, this can increase the costs associated with a boom mechanism. A boom can be directed by a user's hand or connected to the user's head to free the hands. However, for applications, which need extended use, a head-mounted device can tire the user. In addition, a head-mounted solution is also not very practical if the display needs to be put on and taken off frequently.        